The present disclosure relates to systems and methods for monitoring mechanical forces. More particularly, the present disclosure relates to systems and methods for monitoring mechanical forces applied to wound site repairing structure at a wound site.
Wound site repairing structure includes surgical sutures, which are typically threads applied to a wound site using a needle to hold body tissues together. Surgical sutures can be permanent or temporary, and can be made of degradable or non-degradable materials depending on the type of wound. Permanent, or non-degradable, sutures are typically used for closing a skin wound, and may be removed after the wound heals. Permanent sutures can also be used internally for applications that require strong mechanical support for the tissues over a long period of time. In contrast, temporary sutures, which are biodegradable, are used for smaller wounds that exhibit a faster healing time. Depending on the severity and location of the wound, the number of sutures used, and surgical techniques that are practiced, some surgical sutures may experience a large tensile force that may cause them to fail or further tearing of the tissue.
A number of sensors have been designed for monitoring forces and other conditions at wound sites during and after surgery. For example, stitch-force sensors and hook-force sensors monitor the tension of a suture prior to wound closure. The sensor systems can guide surgeons to apply the correct tension on the suture. The correct amount of tension is important because an excessively tight suture can lead to ischemia of tissue and a loose suture is unable to provide a proper mechanical support for the wound. Although such sensors are accurate, they cannot be used to monitor wound conditions, including tension on the suture, postoperatively.
A flexible sensor system, made of integrated single crystal silicon nanomembrane electronics, can be incorporated within a suture to monitor pressure and temperature and to generate heat in the area around the suture. However, this sensor is not designed to monitor the tensile force on the suture. Rather, this sensor monitors the conditions near the wound site. In addition, this sensor requires direct connection to a power supply and data acquisition system, which prevents it from long-term monitoring of a suture at a closed wound.
The ability to track conditions of orthopedic injury sites is very useful for improving treatment outcomes. Current sensor technologies do not allow for real-time tracking of internal injury sites. Standard sensors cannot directly measure stress and/or strain at internal muscles or tendons, while imaging methods such as magnetic resonance imaging, x-ray, and ultrasound cannot be deployed accurately while in motion or around metallic implants.
It would therefore be desirable to have a system and method to provide for postoperative in vivo monitoring of mechanical forces. Such a system may prevent excessive force from damaging the wound repairs and may be used to gain useful information for improving surgical techniques for wound repair as well as in post-operative care.